This invention relates to industrial heat recuperators, and more particularly relates to a heat recuperative apparatus employing a ceramic cross-flow heat recuperator for use on furnaces, ovens and preheaters.
Recent concern about energy conservation and rising fuel costs has caused renewed interest in industrial recuperators to recover waste heat losses and preheat incoming combustion air to increase the efficiency of furnaces, ovens, and preheaters.
While such recuperators are usually constructed from metal parts, the ceramic recuperator has several advantages over conventional metallic recuperators. For example, ceramics in general have high corrosion resistance, high mechanical strength at elevated temperatures, low thermal expansion coefficients (TEC'S) and good thermal shock resistance, and thus exhibit excellent endurance under thermal cycling; are light in weight (about 1/3 the weight of stainless steel); and are cost competitive with high temperature alloys.
Furthermore, ceramic recuperators are available in a variety of shapes, sizes, hydraulic diameters, (hydraulic diameter is a measure of cross-sectional area divided by wetted perimeter) and compositions. Because their TEC'S are typically lower than those of most metals and alloys, however, ceramic recuperators present a compatibility problem to the design engineer desiring to incorporate them into existing furnace, oven and preheater structures.